Apparatus for electrical precipitation



March 3, 1931. w. Hoss 1,794,616

APPARATUS FOR ELECTRICAL PRECIPITATION Filed May 9. 1928 2 Sheets-Sheet 1 ATTO EYS.

March 3, 1931. w. HOSS APPARATUS FCR ELECTRICAL PRECIPITATION Filed May 9, ,1928 2 Sheets-Sheet 2 a 3 5o 5 47 G m1 'ENTOR.

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Patented Mar. 3, 1931 UNITED STATES PATENT OFFICE WILCHELM HOSS, OF FRANKFORT, GERMANY, ASSIGNOR TO INTERNATIONAL PRE- CIPITATION COMPANY, LOS ANGELES, CALIFORNIA, A CORPORATION OF CALI- FORNIA Application filed May 9, 1928, Serial No.

This invention relates to apparatus for electrical precipitation of suspended particles from gases and particularly to electrical precipitation apparatus in which the gas to be treated is passed successively through a plurality of discharge electrode means and collecting electrode means, and in which the potential difference is graded in the respective precipitator units so as to successively subject thegases to electric fields of different intensities.

The principal object of the invention is to provide a novel arrangement for effecting the above described gradation of potential in the respective precipitator units.

According to this invention the gradation of potential is provided by mounting the electrode means (either the collecting or discharge electrodes or both) of the respective precipitator unitsor of certain of said units upon members composed of semi-conducting or resistance material, or by otherwise interposing layers of semi-conducting or resistance material in the electric circuit of the respective units, and makin such semi-conducting member or layers or the respective units of different or graded resistances, as by difierence in thickness thereof or difference in electricalconductivity.

- The accompanying drawings illustrate embodiments of my invention and referring thereto.

Fig. 1 is a longitudinal section of the upper .portions of the collecting and discharge electrodes of one form of the invention, together with the electrical connections therefor.

Fig. 2 is a horizontal section on line 22 in Fig. 1.

Fig. 3 is a vertical section of another modification of the invention.

Fig. 4 is a section on line 44 in Fig. 3.

Fig. 5 is a longitudinal section of the upper portion of an electrical precipitator showing APPARATUS FOR ELECTRICAL PRECIPITATION 276,431, and in Germany May 28, 1927.

electrode means each comprising one or more rows of fine wires, rods or the like mountedby any suitable supporting frame means indi 8 respectively, said collecting electrode means comprising, for example, plates disposed be-- tween the rows of discharge electrodes and consisting of conducting material such as metal, or of concrete or other semi-conducting material. The collecting electrodes may, however, be of any other suitable shape or construction. p

In order to effect a gradation of potential in the successive precipitator units, the collecting electrode plates in the successive units may be mounted upon blocks or members of semi-conducting or resistance material, such as concrete, wood, or the like, of difi'erent thickness, so that a difi'erent thickness of semi-conducting material is interposed in the electric circuit of the respective units.

For example the'collecting electrodes 6 of the first unit may be mounted upon semiconducting or resistance members 10 which rest in turn upon supporting means 11 and the collecting electrodes 7 of the second unit may be mounted upon semi-conducting or resistance members 12, of less thickness than the members 10, restin upon supporting means '13, while the col ecting electrodes 8 possesses the desired electrical resistance.

. The discharge and collecting electrodes of the successive units are connected through the semi-conducting or resistance means aforesaid to any suitable common source of electric power. Said source of power may COIIIPIlSQ' a step-up transformer 25 whose primary winding is connected as by wires 26 to any suitable source of alternating current at ordinary commercial voltage and whose secondary winding maybe connected by wires 27 to opposite contact members of mechanical rectifier 28.

One of the intermediate contact members of said rectifier may be grounded as at 29 and the supporting means 11, 13 and 15 for the several units of the precipitator may also be grounded as indicated at 30. Wire 32 leads from the discharge electrodes or from any metallic' ducting supporting members 12', while the full potential delivered by the electrical equipment will be maintained between discharge electrodes 3 and collecting electrodes 8 in the third unit.

It will be understood that the discharge.

and collecting electrodes above described may be enclosed in any, suitable housing means and the gas to be treated may be passed in either direction through the successive electric fields. For example, the gas may pass from left to right in Fig. 1, in

which case the gas is subjected to electric fields of successively increasing strength in passing between the discharge and collecting electrodes of the successive units. In passing through these electric fields the suspended particles, such as dust, carried by the gas stream, become electrically charged and are precipitated upon the collecting electrodes whence they fall to the bottom of the precipitator and may be removed in any suitable manner.

The gradation of potential efiected in the above manner may, for-example, be such as to provide fora potential diflerence of 40,000 volts in the first unit, 45,000 in the second unit, and 50,000 volts in the third unit, in which case the resistance members 10 should have a resistance sufiicient to cause a potential drop of 10,000 volts across the same, while the resistance members 12 should have a resistance suflicient to cause a drop in potential of 5,000 volts. a v

The modification shown in Figs. 3 and 4 is similar in principle to that above described, the collecting electrode plates 17, 18 and 19 of successive units being'shown, however, as mounted one above another'instead of alongside one another. Common discharge electrode means 20 are provided for all of said units, and the collecting electrodes for the successive units are mounted upon resistance members of varying thickness, which rest in turn on suitable supporting ledges 21 on housing 22. Collecting electrodes 17, for example, may be mounted upon semi-conducting or resistance blocks 23 and collecting electrodes 18 upon resistance blocks 24 of less thickness than the members 23, while collecting electrodes 19 may rest directly upon the housing. The housingmay be grounded as indicated at 30 and the discharge electrode system may be connected by wire 32 to the high tension side of a source of current which may, for example, be the same as shown in Fig. 1.

In Figs. 5 and 6 I have illustrated the insertion of layers of semi-conducting or resistance material between the high tension line and the discharge electrode systems of the several units ofaprecipita-tor. Inthis case the electrical precipitator is shown as com-' prising a casing 35 in which aremounted three successive groups of discharge and collecting electrodes. The collecting electrodes of the successive groups or units are indicated at 36, 37 and 38, said collecting electrodes being supported in any suitable manner as by means of supporting bars 39. The discharge electrode systems of the successive groups or units are indicated at 40, 41 and 42 respectively, each of said discharge electrode systems comprising a plurality of rows of discharge electrode members 43, such as fine wires .or rods, hung between the respective collecting electrode. Said discharge electrode members may be hung from rods or pipes 44 which in turn are secured to transverse frame members 45. A yoke or other suitable member 46 is secured to theframe member or members 45 for the discharge electrode systems of each'group or section.

The supporting yoke 46 for one group of discharge electrode, such as group 42, rests directly upon the common supporting member or bus bar 47, while the supporting yokes for the other groups of discharge electrodes rest upon semi-conducting or resistance members 48 and 49 respectively which have dif-. ferent values of resistance and which are ,in turn supported by supporting member 47. The supporting member 47 may be supported at its ends upon insulating supports 50 enclosed in suitable casing means 51. The electrical connections may, as shown, be substantially the same as in Fig. 1, the high tension wire 32- being in this case connected to the common supporting member 47, so that the resistance of the semi-conducting members 48 and 49 is inserted in the high tension side,

in series with the respective discharge elec- I being subjected in any case to electric fields of c ommon supporting means and the respective succeslsively increasing (or decreasing) poelectrode means supported thereby. tentia It will be understood that, in any of the scribed my name this 30th da forms above described, the gradation of potential may if desired be obtained by making the layers of resistance or semi-conducting ma rial, in the circuits of the respective units, of materials having difierent conductivities insteadof makin them in different thickness, the result bemg the same in either case.

I claim:

1. An apparatus for electrical precipitation of suspended particles from gases comprising a plurality of electrical precipitator units arranged for passage of gas therethrough in series and each provided with collecting electrode means and discharge electrode means, a common supporting means for one of said electrode means for all of said units, members of semi-conducting material between said common supporting means and the respective electrode means supported thereby, said members constituting th'esole electrical connection between said common supporting means'and said electrode means and having diflerent values of resistance in the respective units, and means electrically. connecting said common supporting means and the other electrode means of the respec 'tive units to a source of electric power.

2. In apparatus for electrical precipitation of suspended particles from gases, a common supporting'means, a plurality of groups of collecting elect'rodemeans supported thereby,

- and seml-conducting members of difierent values of resistance between said common supporting means and the respective groups of collecting electrodes.

3; In an electrical precipitating apparatus,

- a source of electric power, two electrical preofsai semi-conducting cipitating units each comprising discharge electrode means and collecting electrode means, a common supporting means for one of said electrode means for both of said units, means electrically connecting said common supporting means to said source of power, the electrode means of one of said units being mounted in direct electrical connection with said common supporting means, and semiconducting means interposed. between the electrode means of the other unitand said common supporting means and. constituting the sole electrical connection there-between. 4. In an electrical precipitating apparatus,

asource of electric ower, two electrical precipitator units eac electrode means and collecting electrode means a common supporting means for one d electrode means for both of said units, means electrically connecting said common supporting means to said source of power, and means having difierent values of-resistance interposed betweeii'said comprising discharge WE LM HOSS. 

